2: ARGON | it's symbol is AR. | Argon is a colorless, odorless, chemically inactive, monatomic, gaseous element that because of its inertness, is used for filling fluorescent and incandescent lamps and vacuum tubes.

3: Argon is located in group 18 & in period 3. It is nonmetal because it is in the right hand of the staircase. elements in group 18 are Nobel, Inert, Rare gases. they have a full valence shells & they are non-reactive. | Location on the Periodic Table

5: atomic number | -The atomic number: 18(it is shown in Refrence Table) -The atomic mass: 39.948 amu(its shown in Refrence Table) -The mass number: 40 (its shown in Refrence Table) -The number of protons: 18(because it is the same as the atomic number) -The number of neutrons: 22(because the mass # - the # of protons) - The number of electrons: 18( because it is a neutral atom)

7: Oxidation state, ionization energy & electronegativity. | -The oxidation number for argon is 0. All of the noble gases are inert. - An ion is an atom that loose or gain electrons and Argon has a full last shell so it doesn't have to gain or loose electrons. -Ionization energy or Potential energy is the energy necessary to remove an electron from the neutral atom. -Electronegativity is a measure of an atom to attract a bonding pair of electrons. - the ionization energy of argon is 1521 kj/mol which is high because it have a stable electron configuration. -argon it does not have an electronegativity.

8: Isotopes | Isotopes are atoms of the same element that have different number of neutrons in the nuclear therefore different atomic wight. - 3 isotopes of argon exist naturally and thy are: Ar-36 (mass number is 36) Ar-38 (mass number is 38) Ar-40 (mass number is 40) | the mass number represents the number of protons + neutrons in the nucleus of an atom of the element. | - Seeing as the molecular weight of argon is very close to 40 g/ml so most common isotope is Ar-40. | - Argon does not have a specific use.

9: The discovery Argon was discovered in 1894. However, English scientist Henry Cavendish (1731-1810) had predicted the existence of argon 200 years earlier. When Cavendish removed oxygen and nitrogen from air, he found that a very small amount of gas remained. He thought that another element was in the air, but he was unable to identify what it was. When Ramsay repeated Cavendish's experiments in the 1890s, he, too, found a tiny amount of unidentified gas in the air. But Ramsay had an advantage over Cavendish: he could use spectroscopy, which did not exist in Cavendish's time. Spectroscopy is the process of analyzing light produced when an element is heated. Ramsay studied the spectrum of the unidentified gas. He found a series of lines that did not belong to any other element. He was convinced that he had found a new element. | Henry Cavedish

10: The name argon comes from the Greek word argos, "the lazy one." The name is based on argon's inability to react with anything. The discovery of argon created a problem for chemists. It was the first noble gas to be discovered. Where should it go in the periodic table? At the time, the table ended with Group 17 (VIIA) at the right. Ramsay suggested that the periodic table might have to be extended. He proposed adding a whole new group to the table. That group would be placed to the right of Group 17 (VIIA). That was accepted and argon was added to a new group. Years later scientists were trying to discover other elements that belong in the same group as argon does.Meanwhile, Rayleigh made his discovery at about the same time Ramsay did. They decided to make their announcement together.

11: Discovery: compound or free element? | -It was discover as a compound because the scientists removed oxygen & nitrogen from air and then they discover Argon. | oxygen and nitrogen | argon

12: Uses of Argon - Argon is used in light bulbs, semi-conductor industry, medical lasers etc. | - Argon is used as a protective covering for the filament in light bulb & incandescent lamps.

13: - As much as i read i got that argon is in the lungs, as part of the air everyone breaths but is not present anywhere else in the body. | -Argon is a non toxic gas and initially is not prone to be hazardous.